Aerosol generating article with thick paper

ABSTRACT

An aerosol generating article (10) includes an aerosol generating substrate (20), a filter element (22), and a first paper wrapper (30) and a second paper wrapper (40) circumscribing the aerosol forming substrate. The first paper wrapper having a thickness in a range from 40 about 90 micrometers to about 160 micrometers. The second paper wrapper joining the aerosol forming substrate to a filter element.

The present disclosure relates an aerosol generating article having athick wrapper. The thick wrapper and a second wrapper circumscribe anaerosol generating substrate joining the aerosol generating substrate toa filter element and forming an aerosol generating article.

Aerosol generating articles in which an aerosol generating substrate,such as a tobacco containing substrate, is heated rather than combusted,are known in the art. Typically in such heated aerosol generatingarticles, an aerosol is generated by the transfer of heat from a heatsource to a physically separate aerosol generating substrate ormaterial, which may be located in contact with, within, around, ordownstream of the heat source. During use of the aerosol generatingarticle, volatile compounds are released from the aerosol generatingsubstrate by heat transfer from the heat source and are entrained in airdrawn through the aerosol generating article. As the released compoundscool, they condense to form an aerosol.

Paper that is used to wrap the aerosol generating substrate and form theaerosol generating substrate element can absorb aerosol former, waterand other liquid compounds found in the mainstream smoke or aerosolpassing through the aerosol generating article, or humidity or moisturesurrounding the paper. The absorbed liquid may stain or weaken the paperand negatively affects the appearance and structural integrity of theaerosol generating article. Heated aerosol generating articles areparticularly susceptible to wetting and breakage due to the high levelsof aerosol former in the aerosol generating substrate of these heatedaerosol generating articles. Heated aerosol generating articles areparticularly susceptible to swelling as aerosol components are absorbedby the wrapper, leading to difficult removal from the heating device.

A resistive heating blade may be inserted into the aerosol generatingsubstrate to heat the aerosol generating substrate and release volatilecompounds from the aerosol generating substrate. The resistive heatingblade may provide a localized heat source within the aerosol generatingsubstrate that may be located along a central axis of the aerosolgenerating substrate. The aerosol generating substrate located about theperiphery or interface with the paper wrapper may not be sufficientlyheated by the centrally located resistive heating blade, resulting inunused aerosol generating substrate within the aerosol generatingsubstrate.

It would be desirable to provide a visually and mechanically stableaerosol generating article, particularly for heat-not-burn aerosolgenerating articles that contain a high level of liquids or aerosolformers. It would also be desirable that this thick paper wrapper orlayer does not affect the taste of the aerosol generated by the aerosolgenerating article.

It would be desirable to provide an aerosol generating article thatreduces the amount of unused aerosol generating substrate within theaerosol generating article.

It would also be desirable that the aerosol generating substrate wrappernot readily burn if proximate a heating element and not negativelyaffect the heating of the heat-not-burn aerosol generating substrate.

A purpose of the invention may be to solve at least partially one ormore of the desirable technical benefits mentioned above.

According to this disclosure, there is provided an aerosol generatingarticle including an aerosol generating substrate, a filter element, anda first paper wrapper and a second paper wrapper circumscribing theaerosol forming substrate. The first paper wrapper having a thickness ina range from about 60 micrometers to about 160 micrometers. The firstpaper wrapper or the second paper wrapper joining the aerosol formingsubstrate to a filter element.

Preferably, an aerosol generating article including an aerosolgenerating substrate, a filter element, and a first paper wrapper and asecond paper wrapper circumscribing the aerosol forming substrate. Thefirst paper wrapper having a thickness in a range from about 90micrometers to about 160 micrometers. The second paper wrapper joiningthe aerosol forming substrate to a filter element.

The first paper wrapper may separate the second paper wrapper from theaerosol generating substrate. The first paper wrapper may not extendbeyond the aerosol generating substrate. The first wrapper extends anentire length of the aerosol generating substrate. The second paperwrapper may join the aerosol generating substrate to the filter element.The first paper wrapper may extend an entire length of the generatingsubstrate. The second paper wrapper may extend less than about 50% ofthe length of the generating substrate.

The second paper wrapper may separate the first paper wrapper from theaerosol generating substrate. The second paper wrapper may not extendbeyond the aerosol generating substrate. The first paper wrapper mayjoin the aerosol generating substrate to the filter element. The firstpaper wrapper may extend an entire length of the generating substrate.

The first paper wrapper may have a paper thickness in a range from about78 micrometers to about 160 micrometers. The first paper wrapper mayhave a paper thickness in a range from about 78 micrometers to about 140micrometers. The first paper wrapper may have a paper thickness in arange from about 90 micrometers to about 140 micrometers. The firstpaper wrapper may have a paper thickness in a range from about 100micrometers to about 140 micrometers. The first paper wrapper may have apaper thickness in a range from about 110 micrometers to about 140micrometers. The first paper wrapper may have a paper thickness in arange from about 125 micrometers to about 140 micrometers. The firstpaper wrapper may have a paper thickness in a range from about 130micrometers to about 140 micrometers.

The second paper wrapper may have a paper thickness that is less thanthe paper thickness of the first paper wrapper. The second paper wrappermay have a paper thickness in a range from about 10 micrometers to about50 micrometers. The second paper wrapper may have a paper thickness in arange from about 10 micrometers to about 35 micrometers. The secondpaper wrapper may have a paper thickness in a range from about 15micrometers to about 30 micrometers. The second paper wrapper may have apaper thickness in a range from about 20 micrometers to about 25micrometers.

The aerosol generating substrate may define a substantially cylindricalshape having a diameter in a range from about 6.8 mm to about 7.1 mm, orfrom about 6.8 mm to about 7.0 mm. The first paper wrapper may have aratio of paper thickness to tobacco substrate diameter in a range fromabout 1:120 to about 1:40. The first paper wrapper may have a ratio ofpaper thickness to tobacco substrate diameter in a range from about1:100 to about 1:50. The first paper wrapper may have a ratio of paperthickness to tobacco substrate diameter in a range from about 1:70 toabout 1:50. The first paper wrapper may have a ratio of paper thicknessto tobacco substrate diameter in a range from about 1:60 to about 1:50.

The aerosol generating substrate may include homogenized tobaccomaterial. The homogenized tobacco material may include tobacco material,from about 1 percent to about 5 percent of a binder, and from about 5percent to about 30 percent of an aerosol-former, in dry weight basis.The aerosol generating substrate may include a gathered sheet ofhomogenized tobacco material that is preferably crimped.

The aerosol generating substrate may include a metallic inductionheating element. The aerosol generating substrate may include aplurality of metallic induction heating elements.

According to this disclosure, there is provided an aerosol generatingsystem comprising, the aerosol generating article, described herein, andan aerosol generating device comprising a heating element configured toheat the aerosol generating substrate.

The heating element may be a resistive heating blade element configuredto be inserted into the aerosol generating substrate. The heatingelement may be an inductive heating element configured to inductivelyheat metallic induction heating elements embedded within the aerosolgenerating substrate.

Advantageously, aerosol generating articles that include a thick wrapperabout the aerosol generating substrate may provide a visually andmechanically stable aerosol generating article, particularly forheat-not-burn aerosol generating articles that contain a high level ofliquids or aerosol formers. As a result, swelling, visible staining andphysical weakening of the wrapper portion of the aerosol generatingarticle may be reduced even when a high level of humectant is includedin the aerosol generating substrate.

Advantageously, aerosol generating substrate elements that include athick wrapper may be formed on conventional aerosol generating articleforming manufacturing equipment. This may improve the processability ofthe aerosol generating substrate elements and reduce manufacturingcosts.

Advantageously, aerosol generating substrate elements that include athick wrapper may increase the amount of aerosol generating substratethat is uniformly heated and consumed, thus reducing unused or wastedaerosol generating substrate material.

Advantageously, aerosol generating substrate elements that include athick wrapper may utilize internal heating of the aerosol generatingsubstrate via induction or resistive heating elements embedded orinserted into the aerosol generating substrate, and the thick paperwrapping the aerosol generating substrate may not negatively affect theheating of the heat-not-burn aerosol generating substrate.

A conventional cigarette is lit when a user applies a flame to one endof the cigarette and draws air through the other end. The localised heatprovided by the flame and the oxygen in the air drawn through thecigarette causes the end of the cigarette to ignite, and the resultingcombustion generates an inhalable smoke. By contrast, in heated aerosolgenerating articles, an aerosol is generated by heating a flavourgenerating substrate, such as tobacco. Known heated aerosol generatingarticles include, for example, electrically heated aerosol generatingarticles and aerosol generating articles in which an aerosol isgenerated by the transfer of heat from a combustible fuel element orheat source to a physically separate aerosol forming substrate. Forexample, aerosol generating articles according to the disclosure findparticular application in aerosol generating systems comprising anelectrically heated aerosol generating device having an internal heaterblade which is adapted to be inserted into the rod of aerosol generatingsubstrate. Aerosol generating articles of this type are described in theprior art, for example, in EP 0822670.

As used herein, the term “aerosol generating device” refers to a devicecomprising a heater element that interacts with the aerosol generatingsubstrate of the aerosol generating article to generate an aerosol.

As used herein, the term “aerosol generating system” refers to acombination of an aerosol generating device and an aerosol generatingarticle.

As used herein, the term “aerosol generating article” refers to anarticle including an aerosol generating substrate that is heated toproduce and deliver inhalable aerosol to a consumer.

The term “aerosol generating substrate element” is used herein to denotean aerosol generating substrate wrapped with a paper layer to form aportion of an aerosol generating article.

The term “aerosol generating substrate” refers to substance capable ofgenerating or releasing an aerosol. The aerosol generating substrate maybe a solid, paste, gel, slurry, liquid, or comprise any combination ofsolid, paste, gel, slurry, and liquid compounds. Preferably the aerosolgenerating substrate is a solid, or a gel composition. The aerosolgenerating substrate may preferably include nicotine.

The term “mouthpiece” is used herein to indicate the portion of theaerosol generating article that is designed to be contacted with themouth of the consumer. The mouthpiece can be the portion of the aerosolgenerating article that may include a filter, or in some cases themouthpiece can be defined by the extent of the tipping wrapper.

The terms “upstream” and “downstream” refer to relative positions ofelements of the aerosol generating article described in relation to thedirection of aerosol as it is drawn from an aerosol generating substrateand through the mouthpiece.

An aerosol generating article includes an aerosol generating substrate,a filter element, and a first paper wrapper and a second paper wrappercircumscribing the aerosol forming substrate. The first paper wrapperhaving a thickness in a range from about 60 micrometres to about 160micrometres. The first paper wrapper or the second paper wrapper joiningthe aerosol forming substrate to a filter element.

The first paper wrapper may separate the second paper wrapper from theaerosol generating substrate. The first paper wrapper may contact theaerosol generating substrate. The first paper wrapper may contact thesecond paper wrapper. The second paper wrapper may not contact theaerosol generating substrate. The first paper wrapper may circumscribethe aerosol forming substrate. The second paper wrapper may circumscribethe first paper wrapper. The second paper wrapper may overlap only aportion of the first paper wrapper. The second paper wrapper may overlapless than about 50%, or less than 25% of the downstream length of thegenerating substrate. The second paper wrapper may join the aerosolgenerating substrate to the filter element. The second paper wrapper maybe referred to as tipping paper. The first paper wrapper may define anupstream outer surface of the aerosol generating article and the secondpaper may define a downstream outer surface of the aerosol generatingarticle. The first paper wrapper may not extend beyond the ends orlength of the aerosol generating substrate. The first paper wrapper mayextend an entire length of the generating substrate.

In another example, the second paper wrapper may separate the firstpaper wrapper from the aerosol generating substrate. The second paperwrapper may contact the aerosol generating substrate. The second paperwrapper may contact the first paper wrapper. The second paper wrappermay circumscribe the aerosol forming substrate. The first paper wrappermay circumscribe the second paper wrapper. The first paper wrapper mayoverlap the entire length of the second paper wrapper. The first paperwrapper may overlap the entire length of the second paper wrapper and becoextensive with the second paper wrapper. The first paper wrapper mayjoin the aerosol generating substrate to the filter element. The firstpaper wrapper may define an entire outer surface of the aerosolgenerating article. The second paper wrapper may not extend beyond theends or length of the aerosol generating substrate. The second paperwrapper may extend an entire length of the generating substrate.

At least about 80%, or at least about 90%, or at least about 95% of theaerosol generating substrate circumference may be circumscribed by lessthan three paper layers. Preferably the less than three paper layers donot extend beyond a length of the aerosol generating substrate.Preferably at least about 80%, or at least about 90%, or at least about95% of the aerosol generating substrate circumference is circumscribedby less than three paper layers which circumscribe the aerosolgenerating substrate along substantially a length of the aerosolgenerating substrate.

The first paper wrapper and the second paper wrapper circumscribe theentire circumference of the aerosol generating substrate with verylittle overlap of each paper wrapper onto itself. An overlap regionforms more than one paper layer, such as two layers for example. Theoverlap region extends along the longitudinal length of the paperwrapper.

Three layers of paper wrapper may be present where the first paperwrapper overlaps itself. Three layers of paper wrapper may be presentwhere the second paper wrapper overlaps itself. The overlap of the firstpaper wrapper and the overlap of the second paper wrapper are preferablyoffset from each other. The overlap of the first paper wrapper and theoverlap of the second paper wrapper are preferably offset from eachother by at least about 45 degrees about the circumference of theaerosol generating substrate. The overlap of the first paper wrapper andthe overlap of the second paper wrapper are preferably offset from eachother by at least about 90 degrees about the circumference of theaerosol generating substrate. The overlap of the first paper wrapper andthe overlap of the second paper wrapper are preferably offset from eachother by about 180 degrees about the circumference of the aerosolgenerating substrate.

The overlap of each paper wrapper onto itself may be about 20% or lessof the circumference of the aerosol generating substrate. This overlapmay be about 15% or less of the circumference of the aerosol generatingsubstrate. This overlap may be about 10% or less of the circumference ofthe aerosol generating substrate. Reducing an overlay or overlap of thepaper may help to prevent or minimize void spaces or air pockets definedbetween the paper layers in an overlap region.

The first paper wrapper may have a paper thickness in a range from about60 micrometers to about 160 micrometers. The first paper wrapper mayhave a paper thickness in a range from about 78 micrometers to about 160micrometers. The first paper wrapper may have a paper thickness in arange from about 78 micrometers to about 140 micrometers. The firstpaper wrapper may have a paper thickness in a range from about 90micrometers to about 160 micrometers. The first paper wrapper may have apaper thickness in a range from about 100 micrometers to about 140micrometers. The first paper wrapper may have a paper thickness in arange from about 110 micrometers to about 160 micrometers. The firstpaper wrapper may have a paper thickness in a range from about 125micrometers to about 140 micrometers. The first paper wrapper may have apaper thickness in a range from about 130 micrometers to about 160micrometers.

The second paper wrapper may have a paper thickness in a range fromabout 10 micrometers to about 50 micrometers. The second paper wrappermay have a paper thickness in a range from about 10 micrometers to about35 micrometers. The second paper wrapper may have a paper thickness in arange from about 15 micrometers to about 30 micrometers. The secondpaper wrapper may have a paper thickness in a range from about 20micrometers to about 25 micrometers.

The aerosol generating substrate may define a substantially cylindricalshape having a diameter in a range from about 6.8 mm to about 7.1 mm.The aerosol generating substrate may define a substantially cylindricalshape having a diameter in a range from about 6.8 mm to about 7.0 mm.

The first paper wrapper may have a ratio of paper thickness to tobaccosubstrate diameter in a range from about 1:120 to about 1:40. The firstpaper wrapper may have a ratio of paper thickness to tobacco substratediameter in a range from about 1:100 to about 1:50. The first paperwrapper may have a ratio of paper thickness to tobacco substratediameter in a range from about 1:75 to about 1:50. The first paperwrapper may have a ratio of paper thickness to tobacco substratediameter in a range from about 1:60 to about 1:50. Conventionallywrapped tobacco substrates may have a ratio of paper wrapper thicknessto tobacco substrate diameter of about 1:300.

The first paper wrapper may have a ratio of paper thickness to tobaccosubstrate element diameter in a range from about 1:100 to about 1:40, orabout 1:75 to about 1:50, or about 1:65 to about 1:50, or about 1:60 toabout 1:50. Conventionally wrapped tobacco substrates may have a ratioof paper thickness to tobacco substrate element diameter of about 1:300.

The first paper wrapper and the second paper wrapper may circumscribethe aerosol generating substrate to define the aerosol generatingsubstrate with a substantially cylindrical shape. The aerosol generatingsubstrate may define a substantially cylindrical shape having a diameterin a range from about 6.8 mm to about 7.1 mm. The aerosol generatingsubstrate element wrapped by the first paper wrapper and the secondpaper wrapper may define a substantially cylindrical shape having adiameter in a range from about 7.1 mm to about 7.3 mm.

The aerosol generating article preferably includes an aerosol generatingsubstrate, a filter element, and a first paper wrapper circumscribingthe aerosol forming substrate and a second paper wrapper circumscribingthe first paper wrapper. The first paper wrapper having a thickness in arange from about 60 micrometres to about 160 micrometres. The secondpaper wrapper joining the aerosol forming substrate to a filter elementand having a thickness in a range from about 20 micrometres to about 40micrometres. The first paper wrapper does not extend beyond the ends ofthe aerosol generating substrate. The first paper wrapper circumscribesan entire length of the aerosol generating substrate. The first paperwrapper and the second paper wrapper each have an overlap of less than20% of the circumference of the aerosol generating substrate. Theaerosol generating substrate has a diameter in a range from about 6.8 mmto about 7.0 mm. Preferably the second paper wrapper circumscribes lessthan about 25% of the downstream length of the aerosol generatingsubstrate.

The aerosol generating substrate element preferably includes an aerosolgenerating substrate having a diameter and a first paper wrapper havinga thickness circumscribing the aerosol generating substrate and at least80%, or at least 90% of the aerosol generating substrate circumferenceis circumscribed by less than three paper layers. Preferably the firstpaper wrapper does not extend beyond the ends of the aerosol generatingsubstrate. Preferably the first paper wrapper circumscribes an entirelength of the aerosol generating substrate. Preferably the ratio offirst paper wrapper thickness to tobacco substrate diameter is in arange from about 1:120 to about 1:40, or about 1:100 to about 1:50, orabout 1:75. Preferably the second paper wrapper circumscribes less thanabout 25% of the downstream length of the aerosol generating substrate.

The aerosol generating article includes the aerosol generating substrateand a mouthpiece. The mouthpiece may comprise a filter. A tippingwrapper (being either the first paper wrapper or preferably the secondpaper wrapper) may join the filter to the aerosol generating substrate.One or more intermediate sections may separate the aerosol generatingsubstrate and a mouthpiece.

The aerosol generating substrate may be a solid composition. Thiscomposition may include plant-based material. The aerosol generatingsubstrate may include tobacco, and preferably the tobacco containsvolatile tobacco flavour compounds, which are released from the aerosolgenerating substrate upon heating. The aerosol generating substrate maycomprise homogenized tobacco material, aerosol former and a binder.

The aerosol generating substrate may include homogenized tobaccomaterial. The homogenized tobacco material may include tobacco material,from about 1 percent to about 5 percent of a binder, and from about 5percent to about 30 percent of an aerosol-former, in dry weight basis.The aerosol generating substrate may include a gathered sheet ofhomogenized tobacco material that is preferably crimped.

Nicotine may be present in the aerosol generating substrate in a rangefrom about 0.5 to about 10% wt, nicotine, or about 0.5 to about 5% wt.nicotine. Preferably the aerosol generating substrate may include about1 to about 3% wt, nicotine, or about 1.5 to about 2.5% wt. nicotine, orabout 2% wt nicotine.

The aerosol generating substrate may comprise any suitable type or typesof tobacco material or tobacco substitute, in any suitable form. Theaerosol generating substrate may include flue-cured tobacco, Burleytobacco, Maryland tobacco, Oriental tobacco, specialty tobacco,homogenized or reconstituted tobacco, or any combination thereof. Theaerosol generating substrate may be provided in the form of tobacco cutfiller, tobacco lamina, processed tobacco materials, such as volumeexpanded or puffed tobacco, processed tobacco stems, such as cut-rolledor cut-puffed stems, homogenized tobacco, reconstituted tobacco, castleaf tobacco, or blends thereof, and the like. The term “tobacco cutfiller” is used herein to indicate tobacco material that ispredominately formed from the lamina portion of the tobacco leaf. Theterms “tobacco cut filler” is used herein to indicate both a singlespecies of Nicotiana and two or more species of Nicotiana forming atobacco cut filler blend.

As used herein, the term “homogenised tobacco” denotes a material formedby agglomerating particulate tobacco. Homogenized tobacco may includereconstituted tobacco or cast leaf tobacco, or a mixture of both. Theterm “reconstituted tobacco” refers to paper-like material that can bemade from tobacco by-products, such as tobacco fines, tobacco dusts,tobacco stems, or a mixture of the foregoing. Reconstituted tobacco canbe made by extracting the soluble chemicals in the tobacco by-products,processing the leftover tobacco fibers into a sheet, and then reapplyingthe extracted materials in concentrated form onto the sheet. The term“cast leaf tobacco” is used herein to refer to a product resulting froma process well known in the art, which is based on casting a slurrycomprising ground tobacco particles and a binder (for example, guar)onto a supportive surface, such as a belt conveyor, drying the slurryand removing the dried sheet from the supportive surface. Exemplarymethods for producing these types of aerosol generating substrates aredescribed in U.S. Pat. Nos. 5,724,998; 5,584,306; 4,341,228; 5,584,306and 6,216,706. The homogenised tobacco may be formed into a sheet whichis crimped, convoluted, folded, or otherwise compressed, before beingwrapped to form a rod. For example, sheets of homogenised tobaccomaterial for use in the invention may be crimped using a crimping unitof the type described in CH-A-691156, which comprises a pair ofrotatable crimping rollers. However, it will be appreciated that sheetsof homogenised tobacco material for use in the invention may be texturedusing other suitable machinery and processes that deform or perforatethe sheets of homogenised tobacco material.

The aerosol generating substrate used in aerosol generating articlesgenerally includes a higher level of aerosol former(s) than combustedsmoking articles, such as cigarettes. Humectants can also be referred toas an “aerosol former”. An aerosol former is used to describe anysuitable known compound or mixture of compounds that, in use,facilitates formation of an aerosol and that is substantially resistantto thermal degradation at the operating temperature of the aerosolgenerating substrate. Suitable aerosol-formers are known in the art andinclude, but are not limited to: polyhydric alcohols, such as propyleneglycol, triethylene glycol, 1,3-butanediol and glycerine; esters ofpolyhydric alcohols, such as glycerine mono-, di- or triacetate; andaliphatic esters of mono-, di- or polycarboxylic acids, such as dimethyldodecanedioate and dimethyl tetradecanedioate. Preferred aerosol formersare polyhydric alcohols or mixtures thereof, such as propylene glycol,triethylene glycol, 1,3-butanediol and, most preferred, glycerine orglycerine. The aerosol generating substrate may comprise a singleaerosol former. Alternatively, the aerosol generating substrate maycomprise a combination of two or more aerosol formers.

The aerosol generating substrate may have a high level of aerosolformer. As used herein, a high level of aerosol former means aerosolformer content that is greater than about 10% or preferably greater thanabout 15% or more preferably greater than about 20%, by weight. Theaerosol generating substrate can also have an aerosol former content ofbetween about 10% and about 30%, from about 15% and about 30%, or fromabout 20% and about 30%, by weight. The aerosol generating substrate canalso have a glycerine content of between about 10% and about 30%, fromabout 15% and about 30%, or from about 20% and about 30%, by weight.

The aerosol generating substrate may comprise at least about 1%, or atleast about 2%, or at least about 5%, or at least about 7%, or at leastabout 10%, or at least about 12%, or at least about 15%, or at leastabout 18% aerosol former, by weight. The aerosol generating substratemay comprise aerosol former in a range from about 1 to about 20%, orabout 5 to about 20%, or about 10 to about 20%, by weight.

The aerosol generating substrate may comprise at least about 1%, or atleast about 2%, or at least about 5%, or at least about 7%, or at leastabout 10%, or at least about 12%, or at least about 15%, or at leastabout 18% glycerine, by weight. The aerosol generating substrate maycomprise glycerine in a range from about 1 to about 20%, or about 5 toabout 20%, or about 10 to about 20%, by weight.

Preferably, the aerosol generating article may be generally cylindrical.This enables a smooth flow of the aerosol. The aerosol generatingarticle may have an outer diameter, for example, between 7.1 millimetresand 7.3 millimetres, or between 7.15 millimetres and 7.25 millimetres.The aerosol generating article may have a length, for example, between10 millimetres and 60 millimetres, between 15 millimetres to 50millimetres, or between 20 millimetres and 45 millimetres.

The aerosol generating substrate may include a flavourant. Botanicalmaterials provide flavourant that may impart a flavour to the taste ofthe aerosol generated by the aerosol generating article. A flavourant isany natural or artificial compound that affects the organoleptic qualityof the aerosol. Non-limiting examples of sources of flavourants includemints such as peppermint and spearmint, coffee, tea, cinnamon, clove,cocoa, vanilla, eucalyptus, geranium, agave, and juniper; andcombinations thereof.

The aerosol generating substrate may include an essential oil. Essentialoils may provide flavourant that may impart a flavour to the taste ofthe aerosol generated by the aerosol generating article. Suitableessential oils include, but are not limited to, eugenol, peppermint oiland spearmint oil. A preferred essential oil is eugenol. Essential oilmay be present in the aerosol generating substrate in an amount of atleast about 0.1% by weight, or at least about 0.5% by weight, or atleast about 1% by weight. Essential oil may be present in the aerosolgenerating substrate in a range from about 0.1% by weight to about 10%by weight, or from about 0.1% by weight to about 5% by weight, or fromabout 0.5% by weight to about 2%.

The aerosol generating substrate may include homogenized tobaccomaterial. The homogenized tobacco material may include tobacco material,from about 1 percent to about 5 percent of a binder, and from about 5percent to about 30 percent of an aerosol-former, on a dry weight basis.Sheets of homogenized tobacco for use in the aerosol-generating articleof the present invention may be made by methods known in the art, forexample the methods disclosed in International patent applicationWO-A-201 2/1 64009 A2. In a preferred embodiment, sheets of homogenizedtobacco material for use in the aerosol-generating article are formedfrom a slurry comprising particulate tobacco, guar gum, cellulose fibresand glycerine by a casting process.

The aerosol generating substrate may include a gathered sheet ofhomogenized tobacco material that is preferably crimped. As used herein,the term “crimped” denotes a sheet having a plurality of substantiallyparallel ridges or corrugations. Preferably, when the aerosol-generatingarticle has been assembled, the substantially parallel ridges orcorrugations extend along or parallel to the longitudinal axis of theaerosol-generating article.

An aerosol generating system may comprise: a heat source; an aerosolgenerating substrate; at least one air inlet downstream of the aerosolgenerating substrate; and an airflow pathway extending between the atleast one air inlet and the mouth-end of the article. The heat sourcemay be integral with an aerosol generating device and a consumableaerosol generating article may be releasably received within the aerosolgenerating device.

The heat source may be a combustible heat source, a chemical heatsource, an electrical heat source, a heat sink or any combinationthereof. The heat source may be an electrical heat source, preferablyshaped in the form of a blade that can be inserted into the aerosolgenerating substrate. Alternatively, the heat source may be configuredto surround the aerosol generating substrate, and as such may be in theform of a hollow cylinder, or any other such suitable form.

Preferably the heat source is configured to heat the aerosol generatingsubstrate directly without transmitting heat to the aerosol generatingsubstrate through the at least one paper layer.

The aerosol generating substrate may include an induction heatingelement or susceptor or a plurality of induction heating elements orsusceptors. Induction heating elements or susceptors heat up in thepresence of an alternating or fluctuating electromagnetic field. Whenheating is by induction heating, a fluctuating electromagnetic field istransmitted through the aerosol generating article to the inductionheating element or susceptor such that the susceptor or inductingheating element changes the fluctuating field into thermal energy thusheating the aerosol generating substrate.

The induction heating element or susceptor may be formed from anymaterial that can be inductively heated to a temperature sufficient togenerate an aerosol from the aerosol generating substrate. The inductionheating element or susceptor may comprises a metal or carbon. Apreferred induction heating element or susceptor may comprise aferromagnetic material, for example ferritic iron, or a ferromagneticsteel or stainless steel. The induction heating element or susceptor maycomprise aluminium. Induction heating element or susceptors may beformed from 400 series stainless steels, for example grade 410, or grade420, or grade 430 stainless 20 steel. Different materials will dissipatedifferent amounts of energy when positioned within electromagneticfields having similar values of frequency and field strength.Preferably, the induction heating element or susceptors are heated to atemperature in excess of 250 degrees Celsius. However, preferably theinduction heating element or susceptors are heated less than 350 degreesCelsius to prevent burning of material in contact with the susceptor.

The aerosol generating substrate may comprise a metallic inductionheating element. The metallic induction heating element may compriseplurality of metallic induction heating elements. The metallic inductionheating element may comprise a metallic induction heating ring element.

The first paper wrapper may exhibit a range of permeability includingnot being permeable. Permeability of cigarette paper is determined byutilizing the International Standard test method ISO 2965:2009 and theresult is presented as cubic centimetres per minute per squarecentimetre and referred to as “CORESTA units”. The permeability of thewrapper described herein may be in a range from about 1 to about 10CORESTA units, about 5 to about 20 CORESTA units, or about 1 to about 5CORESTA units.

The first paper wrapper and the second paper wrapper may each beindependently formed of any cellulosic material such as paper, wood,textile, natural as well as artificial fibers.

The first paper wrapper may comprise a laminate of a paper layer and ametal layer. The first paper wrapper may comprise a laminate of a paperlayer and an aluminium layer. The laminate of a paper layer and analuminium layer may have a uniform thickness in a range from about 78micrometers to about 160 micrometers, or from about 78 micrometers toabout 140 micrometers, or from about 100 micrometers to about 140micrometers, or from about 125 micrometers to about 140 micrometers. Thelaminate of a paper layer and a metal layer may not extend beyond endsof the aerosol generating substrate.

The resistance to draw (RTD) of the aerosol-generating article afterinsertion into the aerosol generating device is preferably between about80 mm WG and about 140 mm WG, more preferably between about 100 mm WGand about 120 mm WG.

As used herein, resistance to draw is expressed with the units ofpressure ‘mm WG’ or ‘mm of water gauge’ and is measured in accordancewith ISO 6565:2002. The resistance to draw (RTD) of the rod ofaerosol-generating substrate is preferably between about 50 mm WG andabout 80 mm WG. Preferably, the RTD of the rod of aerosol-generatingsubstrate is between about 5 mm WG and about 8 mm WG per millimetrelength of the rod.

All scientific and technical terms used herein have meanings commonlyused in the art unless otherwise specified. The definitions providedherein are to facilitate understanding of certain terms used frequentlyherein.

As used in this specification and the appended claims, the singularforms “a”, “an”, and “the” encompass examples having plural referents,unless the content clearly dictates otherwise.

As used in this specification and the appended claims, the term “or” isgenerally employed in its sense including “and/or” unless the contentclearly dictates otherwise.

As used herein, “have”, “having”, “include”, “including”, “comprise”,“comprising” or the like are used in their open-ended sense, andgenerally mean “including, but not limited to”. It will be understoodthat “consisting essentially of”, “consisting of”, and the like aresubsumed in “comprising,” and the like.

The words “preferred” and “preferably” refer to examples of theinvention that may afford certain benefits under certain circumstances.However, other examples may also be preferred under the same or othercircumstances. Furthermore, the recitation of one or more preferredexamples does not imply that other examples are not useful and is notintended to exclude other examples from the scope of the disclosure,including the claims.

FIG. 1A is a schematic cross-sectional diagram of an aerosol generatingarticle.

FIG. 1B is a schematic cross-sectional diagram of another aerosolgenerating article.

FIG. 2 is a schematic cross-sectional diagram of the aerosol generatingsubstrate element along line 2-2 in FIG. 1A.

FIG. 3 is a schematic cross-sectional diagram of the aerosol generatingsubstrate element along line 3-3 in FIG. 2 .

FIG. 4 is a schematic cross-sectional diagram of an aerosol generatingsystem.

FIG. 5 is a schematic cross-sectional diagram a heating blade insertedinto the aerosol generating substrate element.

The aerosol generating articles depicted in FIGS. 1-5 illustrate one ormore examples of aerosol generating articles, components of aerosolgenerating articles, or aerosol generating systems described above. Theschematic drawings are not necessarily to scale and are presented forpurposes of illustration and not limitation. The drawings depict one ormore aspects described in this disclosure. However, it will beunderstood that other aspects not depicted in the drawings fall withinthe scope and spirit of this disclosure.

The aerosol generating article includes an aerosol generating substrate20, a filter element 22, and a first paper wrapper 30 and a second paperwrapper 40 circumscribing the aerosol forming substrate 20. The firstpaper wrapper 30 has a thickness in a range from about 60 micrometers toabout 160 micrometers. The first paper wrapper 30 or the second paperwrapper 40 joins the aerosol forming substrate 20 to a filter element22.

Preferably, the aerosol generating article includes an aerosolgenerating substrate 20, a filter element 22, and a first paper wrapper30 and a second paper wrapper 40 circumscribing the aerosol formingsubstrate 20. The first paper wrapper 30 has a thickness in a range fromabout 90 micrometers to about 160 micrometers. The second paper wrapper40 joins the aerosol forming substrate 20 to a filter element 22.

The aerosol generating article 10, of FIG. 1A and FIG. 1B, illustrateaerosol generating articles 10. FIG. 1A illustrates the first paperwrapper 30 circumscribing the aerosol generating substrate 20 and thesecond paper wrapper 40 circumscribing the first paper wrapper 30 andthe filter element 22. The first paper wrapper 30 extends along theentire length of the aerosol generating substrate 20. The second paperwrapper 40 joins the aerosol generating substrate 20 to the filterelement 22. The second paper wrapper 40 extends onto only a downstreamportion of the first paper wrapper 30.

FIG. 1B illustrates the second paper wrapper 40 circumscribing theaerosol generating substrate 20 and the first paper wrapper 30circumscribing the second paper wrapper 40 and the filter element 22.The first paper wrapper 30 joins the aerosol generating substrate 20 tothe filter element 22. The first paper wrapper 30 is coextensive withthe second paper wrapper 40 along the entire length of the aerosolgenerating substrate 20 from the distal end 13 to a proximal end 11.

An intermediate section 24 separates a filter element 22 from theaerosol generating substrate element 12. The aerosol generatingsubstrate 12, intermediate section 24, and a filter element 22 arealigned from a distal end 13 to a proximal end 11 in serial order andform a cylinder. The second paper wrapper 40 or the first paper wrapper30 circumscribes the aerosol generating article 10 to join the aerosolgenerating substrate element 12 to the intermediate section 24, and afilter element 22.

The intermediate section 24 may comprise on or more of, a hollowcellulose acetate tube or a polylactic acid filter segment. The filterelement 22 may define a mouthpiece segment and be formed of celluloseacetate material. The aerosol generating substrate element 12, theintermediate section 24, and a filter element 22 may be individuallywrapped with a paper layer and then joined to each other with the secondpaper wrapper 40 or the first paper wrapper 30. In particular, theaerosol-generating substrate element 12 is wrapped with the second paperwrapper 40 or the first paper wrapper 30, as described herein.

The aerosol generating article 10 has a mouth end or proximal end 11 andan upstream, distal end 13 located at the opposite end of the article tothe mouth end 11. The aerosol generating article 10 shown in FIG. 1A andFIG. 1B are particularly suitable for use with an electrically operatedaerosol generating device comprising a heater for heating the aerosolgenerating substrate element 12.

FIG. 2 is a schematic cross-sectional diagram of the aerosol generatingsubstrate element 12 along line 2-2 in FIG. 1A. FIG. 3 is a schematiccross-sectional diagram of the aerosol generating substrate element 12along line 3-3 in FIG. 2 .

The first paper wrapper 30 circumscribes the aerosol generatingsubstrate 20 to define the aerosol generating substrate element 12 witha substantially cylindrical shape. The second paper wrappercircumscribes the first paper wrapper 30 to define a substantiallycylindrical shape

The aerosol generating substrate 20 defines a substantially cylindricalshape having a diameter 23 in a range from about 6.8 mm to about 7.1 mm.The aerosol generating substrate element 12 defines a substantiallycylindrical shape having a diameter 33 in a range from about 7.1 mm toabout 7.3 mm or from about 7.15 mm to about 7.25 mm.

The first paper wrapper 30 has a thickness T in a range from about 60micrometers to about 160 micrometers. The first paper wrapper 30 maypreferably have a thickness in a range from about 78 micrometers toabout 160 micrometers, or about 78 micrometers to about 140 micrometers,or from about 100 micrometers to about 140 micrometers, or from about125 micrometers to about 140 micrometers.

The first paper wrapper 30 has a ratio of paper thickness T to tobaccosubstrate diameter 23 in a range from about 1:120 to about 1:40, orabout 1:100 to about 1:50, or from about 1:70 to about 1:50, or about1:60 to about 1:50.

The first paper wrapper 30 circumscribes the entire circumference of theaerosol generating substrate 20 with very little first overlap 100 ofthe first paper wrapper 30 onto itself. The first overlap 100 regionforms more than one paper layer. In FIG. 2 , the first overlap 100 formstwo layers of paper. The first overlap 100 may be about 20% or less ofthe circumference of the aerosol generating substrate 20. The firstoverlap 100 may be about 10% or less of the circumference of the aerosolgenerating substrate 20. The first overlap 100 may be about 5% or lessof the circumference of the aerosol generating substrate 20. The firstpaper wrapper 30 may not extend beyond the ends 25, 26 of the aerosolgenerating substrate 20. The first paper wrapper 30 circumscribes anentire length of the aerosol generating substrate 20 between the ends25, 26 of the aerosol generating substrate 20.

The second paper wrapper 40 circumscribes the entire circumference ofthe first paper wrapper 30 with very little second overlap 101 of thesecond paper wrapper 40 onto itself. The second overlap 101 region formsmore than one paper layer. In FIG. 2 , the second overlap 101 forms twolayers of paper. The second overlap 101 may be about 20% or less of thecircumference of the aerosol generating substrate 20. The second overlap101 may be about 10% or less of the circumference of the aerosolgenerating substrate 20. The second overlap 101 may be about 5% or lessof the circumference of the aerosol generating substrate 20. The secondpaper wrapper 40 may extend beyond the downstream end 26 of the aerosolgenerating substrate 20. The second paper wrapper 40 circumscribes onlya downstream about 25% of the entire length of the aerosol generatingsubstrate 20 between the ends 25, 26 of the aerosol generating substrate20.

The first overlap 100 region is offset from the second overlap 101region by at least about 45 degrees about the circumference of theaerosol generating substrate 20.

FIG. 2 illustrates that where the second paper wrapper 40 overlays thefirst paper wrapper 30, each paper wrapper forms substantially singleturn or single layer around the circumference of the aerosol generatingsubstrate 20. At least about 80%, or at least about 90%, or at leastabout 95% of the aerosol generating substrate 20 circumference iscircumscribed by less than three paper layers or wrappers 30, 40. Atleast about 80%, or at least about 90%, or at least about 95% of theaerosol generating substrate 20 circumference is circumscribed by lessthan two paper layers or wrappers that do not extend beyond a length orthe ends 25, 26 of the aerosol generating substrate 20. At least about80%, or at least about 90%, or at least about 95% of the aerosolgenerating substrate 20 circumference is circumscribed by less than twopaper layers or wrappers which circumscribe the aerosol generatingsubstrate 20 along substantially a length or the entire length of theaerosol generating substrate 20.

FIG. 4 is a schematic cross-sectional diagram of an aerosol generatingsystem 201. FIG. 5 is a schematic cross-sectional diagram a heatingblade 230 inserted into the aerosol generating substrate element 12. Theaerosol generating article 10 may be used with the aerosol generatingdevice 200 as illustrated in FIG. 4 and FIG. 5 .

The aerosol generating device 200 includes a housing 210 defining thereceptacle 220, which is configured to receive the aerosol generatingarticle 10. The aerosol generating device 200 also includes a heatingblade element 230 configured to pierce the aerosol generating substrateelement 12 of the aerosol generating article 10. The heating bladeelement 230 may comprise an electrically resistive heating component. Inaddition, the device 200 includes a power supply 240 and controlelectronics 250 that cooperate to control heating of heating bladeelement 230.

The aerosol generating article 10 illustrates an aerosol-generatingsubstrate element 12, an intermediate section 24, and a filter element22 aligned from a distal end 13 to a proximal end 11 in serial order andform a cylinder. The distal end 13 of the aerosol generating article 10.The aerosol generating substrate 12 has a length of about 12millimetres. The aerosol generating substrate 12 is cylindrical in shapeand has a substantially circular cross-section. The aerosol generatingsubstrate 12 may comprise a gathered sheet of homogenised tobaccomaterial. The sheet of homogenised tobacco material may comprise about10 percent by weight on a dry basis of glycerine. The intermediatesection 24 may be a hollow cellulose acetate tube having a length ofabout 8 millimetres and a thickness of 1 millimetre. The mouthpiecesegment or filter element 22 may comprises a plug of cellulose acetatetow of 8 denier per filament and has a length of about 7 millimetres.

FIG. 5 illustrates the heating blade element 230 disposed within theaerosol generating substrate 12, 20. The heating blade element 230 mayheat the aerosol generating substrate 12 of the aerosol generatingarticle 10. Heating of the aerosol generating substrate 12 causes theaerosol generating substrate 12 to generate an aerosol containing thenicotine which can transfer out of the aerosol generating article 10 atthe proximal end 11.

The heating blade element 230 may have a width 233 of about 5 mm. Theaerosol generating substrate 20 defines a substantially cylindricalshape having a diameter 23 in a range from about 6.8 mm to about 7.1 mm,or about 6.9 mm to about 7.0 mm. The aerosol generating substrateelement 12 defines a substantially cylindrical shape having a diameter33 in a range from about 7.1 mm to about 7.3 mm, or about 7.15 mm toabout 7.25 mm. The heating blade element 230 may lie within about 1 mmfrom the first paper wrapper 30.

In some examples the heating mechanism may be by induction where theheating element emits radio-magnetic radiation which is absorbed by oneor more metallic induction heating elements when the aerosol generatingarticle 10 is positioned in the receptacle 220 of the aerosol generatingdevice 200.

Once the aerosol generating article 10 is releasably received in theaerosol generating device 200 and on the heating blade element 230, theaerosol generating device 200 is actuated to heat the aerosol generatingsubstrate 12 to a temperature of approximately 375 degrees Celsius. As auser draws on the mouth end 11 of the aerosol generating article 10, thevolatile compounds evolved from the aerosol generating substrate 12 aredrawn downstream through the aerosol generating article 10 and condenseto form an aerosol that is drawn through the mouthpiece 11 of theaerosol generating article 10 into the user's mouth.

The examples described above are not limiting. Other examples consistentwith the these described above will be apparent to those skilled in theart.

1. An aerosol generating article comprising: an aerosol generatingsubstrate; a filter element; and a first paper wrapper and a secondpaper wrapper circumscribing the aerosol forming substrate, the firstpaper wrapper having a thickness in a range from about 90 micrometers toabout 160 micrometers; and the second paper wrapper joining the aerosolforming substrate to a filter element.
 2. The aerosol generating articleaccording to claim 1, wherein the first paper wrapper separates thesecond paper wrapper from the aerosol generating substrate.
 3. Theaerosol generating article according to claim 1, wherein the first paperwrapper extends an entire length of the aerosol generating substrate. 4.The aerosol generating article according to claim 1, wherein the firstpaper wrapper has a paper thickness in a range from about 100micrometers to about 140 micrometers.
 5. The aerosol generating articleaccording to claim 1, wherein the second paper wrapper has a paperthickness in a range from about 10 micrometers to about 50 micrometers.6. The aerosol generating article according to claim 1, wherein thefirst paper wrapper does not extend beyond the aerosol generatingsubstrate.
 7. The aerosol generating article according to claim 1,wherein the aerosol generating substrate defines a substantiallycylindrical shape having a diameter in a range from about 6.8 mm toabout 7.1 mm.
 8. The aerosol generating article according to claim 1,wherein the first paper wrapper has a ratio of paper thickness totobacco substrate diameter in a range from about 1:120 to about 1:40. 9.The aerosol generating article according to claim 1, wherein the aerosolgenerating substrate comprises homogenized tobacco material.
 10. Theaerosol generating article according to claim 9, wherein the homogenizedtobacco material comprises tobacco material, from about 1 percent toabout 5 percent of a binder, and from about 5 percent to about 30percent of an aerosol-former, in dry weight basis.
 11. The aerosolgenerating article according to claim 1, wherein the aerosol generatingsubstrate comprises a metallic induction heating element.
 12. Theaerosol generating article according to claim 1, wherein the aerosolgenerating substrate comprises a plurality of metallic induction heatingelements.
 13. An aerosol generating system comprising, the aerosolgenerating article according to claim 1 and an aerosol generating devicecomprising a heating element configured to heat the aerosol generatingsubstrate.
 14. The aerosol generating system according to claim 13,wherein the heating element is a resistive heating blade elementconfigured to be inserted into the aerosol generating substrate.
 15. Theaerosol generating system according to claim 13, wherein the heatingelement is an inductive heating element configured to inductively heatmetallic induction heating elements embedded within the aerosolgenerating substrate.
 16. The aerosol generating article according toclaim 5, wherein the first paper wrapper has a paper thickness in arange from 125 micrometers to about 140 micrometers.
 17. The aerosolgenerating article according to claim 1, wherein the first paper wrapperhas a paper thickness in a range from 100 micrometers to about 140micrometers, and the second paper wrapper has a paper thickness in arange from about 10 micrometers to about 35 micrometers.
 18. The aerosolgenerating article according to claim 17, wherein the first paperwrapper has a ratio of paper thickness to tobacco substrate diameter ina range from about 1:100 to about 1:50.
 19. The aerosol generatingarticle according to claim 16, wherein the aerosol generating substratecomprises a plurality of metallic induction heating elements.
 20. Theaerosol generating article according to claim 17, wherein the aerosolgenerating substrate comprises a plurality of metallic induction heatingelements.